As is well known to those skilled in the art, it is a concern in car assembly plants, and more specifically engine assembly plants, to obtain a perfect tightness during assembly of the fluid pipings and conductors, irrespective of the flammability of the fluid.
As is well known, the assembly of such hoses in their respective connectors is made by fitting axially and under pressure the end of the hose provided with annular radial enlargement, the male backpiece, to the female connection body. The locking with respect to each other is made by a laminar lock which actuates with respect to the male backpiece and the female body, based on movement in a plane perpendicular to the central axis of the coupling members.
The connections used for coupling these hoses may have different shapes, such as elbow, "T"-shaped, "Y"-shaped, depending on the direction of the passing fluid, which may be a flammable fuel, such as gasoline, diesel or alcohol, or may be a lubricating or hydraulic fluid, such as a motor oil, brake fluid or hydraulic steering fluid, or may be even a refrigerating fluid, such as radiator water or solution for sealed radiators.
Although it ensures the axial retention between the parts, a drawback of this conventional method of axial fit and radial locking between the male backpiece and the female body of the vehicle fluid communication line is that it is not possible to find out whether the outermost edge of the male backpiece has reached its end of travel relative to the housing or seat defined within the female body during the axial connection between them. The potentially spaced apart coupling of such pieces may cause leakages to occur which might result in serious problems.
It is obvious that a bad connection of any one of the fluid conduction lines existing in a vehicle may cause serious problems and even accidents due to a mechanical failure of the vehicle caused by fluid leakage.